The present invention relates to a fuel injector.
A fuel injector is referred to in German Patent Application No. 197 36 682, in which a guide and seating area, which are formed from three disk-shaped elements, are provided on the downstream end of the valve. A swirl element is imbedded between a guide element and a valve seat element. The guide element guides an axially movable valve needle projecting through the guide element, and a valve closing section of the valve needle cooperates with a valve-seat surface of the valve seat element. The swirl element has an inner opening area containing a plurality of swirl channels, which are not connected to the outer periphery of the swirl element. The entire opening area extends completely over the axial depth of the swirl element.
In addition, a fuel injector is referred to in German Patent Application No. 198 15 789, in which the fuel injector has a swirl disk located downstream from a valve seat, the swirl disk including at least one metallic material and having at least two swirl channels opening into a swirl chamber. All the layers of the swirl disk are adhesively deposited by electrodeposition (multilayer metallization), one on top of the other. The swirl disk is installed in the valve, so that its surface normal extends diagonally to the longitudinal axis of the valve at an angle deviating from 0xc2x0 is obtained by aligning the swirl disk so that a jet angle xcex3, with respect to the longitudinal axis of the valve.
It is believed that a disadvantage of the fuel injectors described above is the high cost associated with complicated manufacturing requirements. Modifying the fuel injector for a desired use may require the use of complicated manufacturing procedures. For example, jet angles xcex1 and xcex3 may not be achieved using common swirl generation methods.
It is believed that an exemplary fuel injector according to the present invention has the advantage in that a swirl disk, having individual swirl elements, is easily manufacturable and may be used in standard fuel injectors. The number of swirl elements, as well as the number of overlapping fuel passages forming fuel channels, which impart swirl on the fuel, may be varied as desired and may be easily adapted according to the demands on the fuel injector.
It is also believed to be advantageous in that the swirl disk may be situated either on the inflow side or on the outflow side of the sealing seat, depending on the construction of the fuel injector.
In addition, it is believed that an inclination of the longitudinal axis of the valve-seat member with respect to the longitudinal axis of the fuel injector is advantageous for use in inclined injection.
It is also believed to be advantageous to construct a swirl chamber on the outflow side of the swirl disk, the swirl chamber being suitably dimensioned, so that a homogeneous swirl flow may be formed.
It is also believed to be advantageous to arrange the swirl disk in a plug-in unit, which is insertable into the valve-seat member, since the plug-in unit, as well as a cavity accommodating the plug-in unit, may be easily manufacturable.